Demonstrating device benchmarking for useful quantum applications*

Using a Rydberg atom-array quantum simulator, we experimentally demonstrate new applications which become possible through verifiable quantum evolution, and further develop our recently proposed protocol for estimating the fidelity of producing non-trivial states for this purpose. At the outset, we show experimental benchmarking with as many as 33 qubits with a small (~5000) number of measurements and show potential scaling to as many as 100 qubits. This protocol is then adapted for the application of target state benchmarking, where we prepare interesting quantum states, and quantitatively measure their preparation fidelity. Along similar lines, we demonstrate in situ learning of local Hamiltonian parameters, and progress towards closed-loop optimization of state preparation control. These new developments showcase practically useful applications for device benchmarking protocols in quantum devices, and further demonstrate a path towards quantum advantage with a near term quantum simulator.